Weight-Gain Velocity in Newborn Infants Managed with the Kangaroo Method and Associated Variables

Objectives The Kangaroo method helps promote maternal breastfeeding and adequate growth of low birthweight preterm infants. The objective of this study was to analyze the association between weight-gain velocity during use of the Kangaroo method and maternal and infant variables. Methods A nested cross-sectional study in a cohort of newborn infants managed using the Kangaroo method was carried out at a reference center for the method in Brazil. Data on low birthweight and preterm infants managed using the Kangaroo Method (n = 78) and on their respective mothers (n = 70) was collected between January and July 2014. Maternal and infant variables were associated and correlated with weight-gain velocity (g/kg/day) at each phase of the method (p < 0.05). Results Mean weight-gain velocity increased from 0.12 ± 11.11 g/kg/day in the first phase to 13.47 ± 4.84 g/kg/day in the third phase (p < 0.001), and percentage of adequate weight increased at phase 3 (p < 0.001). Birthweight was inversely correlated with weight-gain velocity at phases 1 and 2 of the Kangaroo method. Birthweight of under 1500 g was associated with a lower likelihood of inadequate weight-gain velocity of the newborn at phase 1 (OR = 0.1; 95 % CI 0.01-0.78; p = 0.012). In phase 3, maternal age was directly correlated with weight-gain velocity. Conclusions Weight-gain velocity was associated with maternal (age) and infant (gestational age at birth, birthweight, weight for gestational age at birth, length of hospital stay and five-minute Apgar score) variables. Knowledge of the factors influencing weight-gain velocity and its behavior at each phase of the method can help guide conduct toward potentializing factors that promote adequate weight-gain.